JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 984 · 40 questions

Code tip (Line by line): let x = 5; makes a variable x holding 5; x = x + 2; changes it to 7. console.log(…) writes in the console; alert(…) shows a pop-up box. Text in quotes + anything = joined text: "5" + 3 → "53".

1. 1.⚡ What does this code print? (Look at the quotes!)
   let x = "3";
   let y = 1;
   console.log(x + y); (a) 4 (b) Error (c) 31
2. 2.⚡ What number does this code print?
   let score = 5;
   score = score + 9;
   score = score - 12;
   console.log(score);
3. 3.⚡ What number does this code print?
   let coins = 21;
   coins = coins + 7;
   coins = coins - 17;
   console.log(coins);
4. 4.⚡ What number does this code print?
   let a = 42;
   let b = 21;
   console.log(a - b);
5. 5.⚡ What does this code show?
   let name = "Kabir";
   console.log("Hi, " + name + "!"); (a) name (b) Hi, Kabir! (c) Hi, name! (d) Kabir
6. 6.⚡ What number does this code print?
   let a = 29;
   let b = 4;
   console.log(a - b);
7. 7.⚡ What number does this code print?
   let a = 12;
   let b = 2;
   console.log(a * b);
8. 8.⚡ What does JavaScript add to a web page? (a) only colours (b) the page title (c) actions and changes (d) the domain name
9. 9.⚡ Which JavaScript word shows a pop-up box? (a) for (b) if (c) console.log() (d) alert()
10. 10.⚡ What number does this code print?
    let coins = 13;
    coins = coins + 5;
    coins = coins - 15;
    console.log(coins);
11. 11.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!"); (a) Kabir (b) Well done, name! (c) Well done, Kabir! (d) name
12. 12.⚡ What does this code show?
    let name = "Aman";
    console.log("Hello, " + name + "!"); (a) Aman (b) Hello, name! (c) Hello, Aman! (d) name
13. 13.⚡ Which JavaScript word repeats code? (a) let (b) for (c) if (d) alert()
14. 14.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Zoya (d) Hello, Zoya!
15. 15.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 8;
    console.log(x + y); (a) Error (b) 58 (c) 13
16. 16.⚡ Which JavaScript word runs code when true? (a) let (b) console.log() (c) if (d) for
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 5;
    console.log(x + y); (a) Error (b) 8 (c) 35
18. 18.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Riya (c) name (d) Welcome, Riya!
19. 19.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <code> (c) <script> (d) <style>
20. 20.⚡ What number does this code print?
    let score = 30;
    score = score + 2;
    score = score - 2;
    console.log(score);
21. 21.⚡ Which JavaScript word makes a new variable? (a) let (b) console.log() (c) if (d) alert()
22. 22.⚡ What number does this code print?
    let marks = 10;
    marks = marks + 16;
    marks = marks - 26;
    console.log(marks);
23. 23.⚡ What number does this code print?
    let a = 12;
    let b = 12;
    console.log(a * b);
24. 24.⚡ What number does this code print?
    let coins = 5;
    coins = coins + 20;
    coins = coins - 22;
    console.log(coins);
25. 25.⚡ What does alert() show? (a) a table (b) a pop-up box (c) a picture (d) a new tab
26. 26.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Kabir! (c) name (d) Kabir
27. 27.⚡ What number does this code print?
    let runs = 11;
    runs = runs + 19;
    runs = runs - 1;
    console.log(runs);
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) 9 (b) Error (c) 18
29. 29.⚡ What number does this code print?
    let a = 46;
    let b = 39;
    console.log(a + b);
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 5;
    console.log(x + y); (a) 12 (b) Error (c) 75
31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y); (a) 11 (b) 29 (c) Error
32. 32.⚡ What number does this code print?
    let score = 28;
    score = score + 15;
    score = score - 40;
    console.log(score);
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y); (a) 7 (b) 61 (c) Error
34. 34.⚡ What number does this code print?
    let a = 7;
    let b = 33;
    console.log(a + b);
35. 35.⚡ What number does this code print?
    let marks = 24;
    marks = marks + 15;
    marks = marks - 32;
    console.log(marks);
36. 36.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the address bar (d) in the console
37. 37.⚡ What number does this code print?
    let a = 38;
    let b = 6;
    console.log(a - b);
38. 38.⚡ What number does this code print?
    let a = 47;
    let b = 26;
    console.log(a - b);
39. 39.⚡ What number does this code print?
    let a = 7;
    let b = 10;
    console.log(a + b);
40. 40.⚡ Which JavaScript word writes in the console? (a) alert() (b) let (c) if (d) console.log()

Free html and css lessons, practice and worksheets at talentjr.in/html-css-for-kids